アルミニウム自然発色皮膜の電子顕微鏡による研究

抄録

Morphology of integrally colored anodic films in some electrolytes such as sulfosalicylic acid+ sulfuric acid, oxalic acid +sulfuric acid, and sulfuric acid has been studied by electron microscope. The electron micrographs of these film sections showed the branched pores developing not exactly perpendicular to the surface and the scallop shaped pore colonies as fiberous bundles. Impurities in metal substrates caused severe disorder of cellular structure of the film around them, which means termination and/or branching of the pore. The initiation process of the film formation at constant voltage is assumed as follows; (1) barrier type film is formed, and (2) branching pore colonies appear in some places subsequent to final dense pore development on the barrier film. Apparently there exists a correlation between intensity of color and disorder of cellular structure of the films.